Well the Unreal 4 Tech Demo batch has been leaked by someone or released by Epic for people to try. Links to download are: http://www.techpowerup.com/downloads/2369/unreal-engine-4-five-tech-demos/ http://www.techpowerup.com/downloads/2368/unreal-engine-4-elemental-tech-demo/ Please note before running the above demos you might have to install the (included) Microsoft Visual C++ 2013 Redist Runtimes, x64 & x86. Settings can be edited using the included batch file (e.g. ResolutionSizeX=1920; ResolutionSizeY=1080) Runs on my pc at 1080p 60fps solid apart from on the Elemental Demo where it dips down to just over 30fps at one point, but it seems like Vsync is enabled even though it's turned of in the .ini file. Runs only on a single card as well and only used my cpu up 40% max. Here are some videos I recorded. Enjoy
Ran like a slideshow ~30fps on mine... pushing my cpu into the 60c range which is ridiculous for me since it's on water and gpu into 80c+ but I did set it to 1440p, use native, fullscreen. It is really nice looking though with some cool effects.